Cause #1: The Crusades
During the Crusades Christian Europeans would travel to the holy land to fight the Turks(Muslims) over the land. While being in the holy land they were introduced to new spices and clothes, leading them to find out about a trade route called the Silk Road. Later the Turks blocked the Europeans access to the silk road, and the new things that they had just found out about. This forces the Europeans to find a new way to gain access to these new things that they loved. While looking for a way to get to China where the Silk Road is located, they "discovered" an area that would later be known as North America. By "discovering" this land exploration is pushed forward, because this shows that there is a lot that they have never seen hat needs to be discovered.
Cause #2: Technology
During the Age of Exploration there were 5 major technological advances, the astrolabe, magnetic compass, caravel, sextant and Mercator's projection. The caravel was a ship that had many uses such as, cargo ships, warships, patrol or dispatch boats, and also pirate ships. With these ships having so many uses it made trade and exploring much easier to do. With trade you discover new areas to gain more resources and share theirs. The sextant is a device that measures the angle between two objects, by having this explorers can see almost exactly how far they are from an area that they have never been to. This technological advance made exploration easier by showing them where they are at relative to what is around them and how far away it is.